Spinning centrifugal forces

Cyclones. Cyclones are also primarily used as prefilters. These also were discussed in Chap. 3 and illustrated in Fig. 3.4. The particle-laden gas enters tangentially and spins downward and inward, ultimately leaving the top of the unit. Particles are thrown radially outward to the wall by the centrifugal force and leave at the bottom. 

Fig. 5. Separation in Latham bowl (a) whole blood is pumped down the feed tube and enters bowl at bottom (b) centrifugal force spins denser cellular components outside, leaving plasma or platelet-rich plasma (PRP) in inner band (c) when bowl is full, plasma flows out effluent tube, followed by platelets and then leukocytes, until bowl is almost completely full of ted cells (d) after draw is completed, bowl stops spinning and uncoUected components are...

In this case, a controlled quantity of water is discharged against a rapidly rotating disk where centrifugal force spins the droplets radially against circumferentially placed baffles, producing a fine water mist which is discharged into the airstream. 

Nutation. The axis of a spin-stabilized projectile in flight is subject to spasmodic small conical vibrations, called nutation, which should not be confused with yaw (qv) or precession (qv). The instant a spinning projectile leaves a gun, the turbulence produced by the release of proplnt gases causes nutations to occur. Their amplitude is usually small, and, in the case of concentric fast spinning projectiles, they disappear due to the action of equal and opposite centrifugal forces. 

Forced-flow development enables the mobile phase velocity to be optimized without regard to the deficiencies of a capillary controlled flow system [34,35). In rotational planar chromatography, centrifugal force, generated by spinning the sorbent layer about a central axis, is used to drive the solvent... 

Centrifugal force is used to introduce molten metal into a mold cavity that is spinning around its axis. Cast iron pipe is produced in centrifugal molds, and copper-base alloy bearings are also commonly produced this way. Permanent metal molds are usually coated or lined to extend operating life. 

Under the influence of a gravitational (centrifugal) field, a solute particle of mass m — M/Ni immersed in a solvent of density p at a distance r from the rotor axis experiences three forces. Within the frame of reference of the rotor, spinning with angular velocity co, these are the centrifugal force Fc, the buoyant force Fb, and the frictional force Ff. 

The theory behind this coating technique involves the equilibrium between the centrifugal forces created by the rapid spinning and the viscous forces determined by the viscosity of the liquid.1,88 Die film thickness can be varied by controlling the spin speed and time, as well as the viscosity of the solution. 

The use of a rotating reactor to provide efficient mixing has been proposed and tested for viscous polymerizations and acid-catalysed rearrangement reactions [6], The principle of these spinning disc reactors is that the centrifugal force... 

It is the aim of this section to offer but a brief introduction to this relatively new field of endeavour that will surely have a not inconsiderable role in shaping the whole future of both physical and chemical processing. It may be noted at the outset, however, that it is not the use of centrifugal forces which is a relatively new development, but rather their application in spinning discs and indeed, centrifugal devices are already widely used in processing, as indicated by the following examples ... 

The catalyst is mixed with air where it picks up oxygen atoms, then is blown together with butane into a reactor where the chemical reaction takes place. The effluent from the, reactor is a mixture of catalyst, MA, water vapor, and a little feedstock. The catalyst is removed by a contraption called a cyclone, which uses centrifugal force to spin the solid., heavier catalyst particles out of the mixture. The MA and feedstock (butane, etc.) are then separated for recovery (the MA) or recycle (the feedstock). 

In a spin-filter based stirred bioreactor, there are various forces acting on both the liquid medium and the cell particles gravity force, axial force due to impeller rotation, centrifugal force created by the spin-filter rotation, and radial force (drag) generated by the perfusion flux. 

The SpinTek technology involves membranes that are bonded to two sides of a disk. Multiple disks are mounted on a hollow shaft that rotates the membranes, and stationary turbulent promoters are mounted near the rotary membranes to create high shear and turbulence. Liquid waste is pumped into the system that hits the spinning disk and spreads across the membrane. Centrifugal force pulls the solid waste outward to the perimeter of the filter disks, where it is removed from the system. By pulling the solids outward, the centrifugal force keeps the filter clear so that the system can run continuously. 

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